Various technologies are used for uniquely identifying a person in accordance with an examination of particular attributes of either the person's interior or exterior eye. One of these technologies involves the visual examination of the particular attributes of the exterior of the iris of at least one of the person's eyes. The iris of the human eye has random patterns of striations, ciliary processes, crypts, rings, furrows and other features which had been shown capable of generating highly unique biometric templates for personal identification. In this regard, reference is made to U.S. Pat. No. 4,641,349, "Iris Recognition System", issued to Flom et al., and U.S. Pat. No. 5,291,560, "Biometric Personal Identification System Based on Iris Analysis", issued to Daugman. As made clear by these patents, the visible texture of a person's iris can be used to distinguish one person from another with great accuracy. Thus, iris recognition can be used for such purposes as controlling access to a secure facility or a bank automatic teller machine, for example. An iris recognition system involves the use of an imager to video image the iris of each person attempting access, and image processing means for comparing this iris video image with a reference iris image on file in a database.
Iris identification systems have been developed that are capable of collecting images of the iris and processing them to produce biometric templates. These templates may be used to identify individual irises with extremely low error rates, on the order of 1 in 10.sup.78. The systems capture the iris images using stationary optical platforms that are often large, complex, and expensive. The systems are difficult to use with minimal cooperation of the subject being identified. As a result their usefulness in many applications is limited.
Although the art of human recognition systems is well developed, there remain some problems inherent in this technology, particularly the lack of a portable or handheld device specifically designed to solve the problems inherent in capturing a close-up, high-quality, properly focused image of the iris of the eye. Therefore, a need exists for a recognition system that overcomes the drawbacks of the prior art.